Re: It's a bug? Re: Strange problem
>>att: 4.09999999999999964473
>>b: (att-floor(att) * 10) 0.99999999999999644729
>>a: (floor(b)) 0.00000000000000000000
>>att: 5.09999999999999964473
>>b: (att-floor(att) * 10) 0.99999999999999644729
>>a: (floor(b)) 0.00000000000000000000
>
>That explains why, as I was puttering with the code last night,
>if I made "att" slightly larger-- say 4.11 that the conversion worked...
>
Irv,
According to the book, we only get 16 places of accuracy from a
64 bit float. Your float routine is printing 20 places. It looks to me
as if you could add something small way past any point of concern
depending on the equation, such as 0.00000000001 and the equation
would work. I'm still interested in those last 4 places. Where are they
being manufactured from? Twenty places is approximately the capacity
of an 8 byte binary integer. A 64 bit float has overhead for the exponent.
Also, the number is not accurate to 16 places, but 14. Curiouser and
curiouser said "Alice".
The thing that matters is how to know when it is going to be a 32 bit or
a 64 bit float and how to get rounding routines to work to the accuracy
that is wanted for any particular mathematical situation.
Everett L.(Rett) Williams
rett at gvtc.com
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